<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title></title>
  <style>
    .dropdown {
      position: relative;
      display: inline-block;
    }
    .dropdown-content {
      display: none;
      position: absolute;
      background-color: #f9f9f9;
      min-width: 160px;
      box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
      padding: 12px 16px;
    }
    .dropdown:hover .dropdown-content {
      display: block;
    }
  </style>
</head>
<body>
<div style="margin-left: 500px">
<div class="dropdown">
  <span>鼠标移动到我这！</span>
  <div class="dropdown-content">
    <p>菜鸟教程</p>
    <p>www.runoob.com</p>
  </div>
</div>
</div>
</body>
</html>
